I think I found my problem after reading this thread: Quota exceeded on dataset <...>/.system/cores - #11 by awalkerix
I have the Immich app running and enabled the CUDA GPU AI thing, but I don’t have a GPU with CUDA support so the Immich was throwing exception. This got exponentially worse when I uploaded a bunch of images.
I’ve disable the CUDA AI stuff and deleted all files in /var/db/system/cores. So far no more warning messages about quotas.